Double regenerative repeater



p 1944- I L. M. POTTS 2,358,100

DOUBLE REGENERATIVE REPEATER I Originl Filed Jan. 18, 1941 3 Sheets-Sheet l INVENTOR. LOUIS M. POTTS ATTORNEY.

Sept. 12, 1944. L, -r5

DOUBLE REGENERATIVE REPEA'IER 3 Sheets-Sheet 2 Original Filed Jan. 18, 1.941

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ISTART l Y STOP sum I STOP A l'lfe I STOP START STOP START STOP START 5 INVENTOR.

LOUIS M.' POTTS m 570p START ATT w- 9 M. POTTS 2,358,100

DOUBLE REGENERATIVE REPEA'ITER Original Filed Jan. 18, 1941 V 5 Sheets-Sheet 5 INVENTOR g LOUIS uLPo'r'rs AT ORNEY Patented Sept. 12, 1944 DOUBLE REGENERATIVE REPEATER.

Louis M. Potts, Evanston, Ill., assignor to Teletype Corporation, Chicago, Ill., a corporation of Delaware Original application January 18, 1941, Serial No.

374,991. Divided and this application November 2, 1942, Serial No. 464,214

12 Claims.

This invention relates to printing telegraph systems and more particularly to regenerative telegraph signal repeaters therefor.

This application is a division of application Serial No. 374,991, filed January 18,1941, now Patent No. 2,339,804, granted Jan..25, 1944..

The primary object of the present invention is to provide a double regenerative repeater for antomatically producing two definitely spaced signal impulses for each received signalimpulse.

Another object of the invention is to provide a regenerative repeater having means to generate a first set of signals corresponding to signals received by said repeater and means to generate a second set of signals identical with but lagging by a predetermined time interval'said first set of regenerated signals.

More specifically, the present invention contemplates the combination ofstructures heretofore separately identified as regenerative repeaters and storing repeaters into asingle unitary 7 transmission of an-integral number of complete signal combinations. Briefly, the device for achieving the objects of the present invention comprises a mechanical repeater of the type shown in United States Patent No; 2,105,173, modified so as to generate two signal impulses in response to each received signal impulse.

A more complete understanding ofthe invention may be-had from the following description taken in connection with the accompanying drawings wherein, v

' Fig. 1 is an elevational view of the repeater mechanism according to the present invention;

Fig. 2 is a sectional view taken on 1ine 2-2 of Fig.3;

' Fig. 3 is a side elevational view of said repeater mechanism; I

Fig. 4 is a detailed view of the armature, taken on line 4-4 of Fig:1; r i

Fig. 5 is a detailed view of the cam sleeves;

Fig. 6 is a perspective View partly exploded of the repeater according to the invention; Fig. 7 is a timing diagram of one mode of operation of the repeater illustrated in Figs. 1 to 6, inclusive; and

Fig. 8 shows telegraph stations interconnected to a central oflice, which circuit arrangement embodies the combination repeater mechanism of the present invention.

Illustrated in Figs. 1 to 6, inclusive is a mechanical regenerative repeater of the form hown and described in United States Patent No. 2,105; 1'73, issued to W. J. Zenner et al.. the .struc' ture of the Zenner et al. patent being modified for the purposes of the present inventionto generate two signalimpulses at the repeater in re sponse to each received signal impulse, the two regenerated signal impulses beingsimilar in nature but displaced in time from one another. Accordingly, the disclosure of the noted Zenner et al. patent is made a part of this, application and will be referred to further herein.

I Referring to Figs. 1 to 6, inclusive, there is shown mounted rigidly on a frame plate .10 a pivot stud l I upon which there oscillateindependently an armature member l2 and first and second repeating members 25 and 35, respectively. 7

The repeater magnet I I3 is provided with an armature I2 of yoke form and pivotally mounted on stud llbyyokearm's l4 and [5 (see Fig. 3). The armature comprises a plurality of extensions, namely, portion 16 which is'attracted directly by themagnet. a first cam follower IT and a second cam follower I8 passing through an opening 23 (see Fig. 4) in frame plate Ill and these followersare controlled by cams B5 and 86, respectively, formechanically. assisting armature 12, a starter striker [9 .on an arm 33-to initiate the operation of the repeating mechanism, a latch lever 20 which is a subextension oncam follower I8 and which determines the delay inserted in the transmission circuit, and a pair of anchor arms 2| and 22 to Whichsprings extend and provide a self centering mechanism for repeater tongue 25 with respect to the arma The regenerative repeater member 25 also pivotally supported bythe stud member I I engages the stud member by yoke arms 24positioned between the yoke arms [4 and I5; 'It is provided with a plurality of operating extensions; namely, a pair of signal repeating electrical contacts 26 to transmit theregenerated signal impulses, a pair of transfer abutments 2 9 and 30 on a lateral arm Z' I'passing through an opening 28 in frame plate 10 to control regenerative-repeater member 35, a lock edge 3| and a jockeyedge 32 to hold repeater member 25 in'its various positions (see Figs. 2, 4, and 6). V A storage repeater member 35 also is pivotally supported by the stud member 1 l, engaging the stud l Iby yokearms 3tand'3l on alternate sides of plate l0 and connected through the web body of the member 35, passing through-an opening in theframe'platekl0. -In front of the frame In,

cated end (see Figs. 2 and 6).

Cooperating with the two repeater members 25 and 35 is a transfer assembly for controlling repeater member 35 to cause it to regenerate and repeat signal impulses and it comprises a transfer lever (see Figs. 1, 2, 3, and 6) 42 pivoted on a fixed post 43 and provided with a cam follower 44 and with an extension arm 45 which carries at its distal end a pivot pin 46. The pivot release cam I on the first cam sleeve 5| and is operated by the cam I5 to operate the lock lever I9 in the manner illustrated and described in the patent to Zenner et al. A further extension arm I8 at the opposite end of lever 8| terminates in a cam follower for the release cam 11 on the second cam sleeve 52 (see Figs. 1, 3, and 6). A spring 49 urges lever 8| counterclockwise, retaining its follower projections against these cams.

Springs 82 and 33 approximately alike in all dimensions, extend respectively from anchor arms 2| and 22 on the armature member I2 to regenpin 46 carries a transfer T 41 which upon beingmoved by the arm 45 under power from cam follower 44 may engage alternatively either the abutment 29 or the abutment 30 on extension arm .21 of. repeater member 25 and be rotated upon its supporting pin 48. V

The particular abutment with which T 41 engagesisdetermined by the position of repeater member'25 That is, if repeater member 25 is in it lower position repeating a spacin impulse, abutment 29 on .extensionl2I of member 25'is in alignment with and will be engaged by T 41, whereas, when a marking impulse is being repeated by member 25, that member is in its upper position and .T 41 will engage abutment 30 (see Fig. 2). Transfer T 41 carries a transfer pin 48 which .at all times is confined .withinthe bifurcaerative repeater member 25, providing a self-centering articulation. IA jockey 9I pivoted at 98 is retained by spring 99 against the described jockey edge 32 on the repeater member 25 (see Figs. 1 and 3). l

C'arn sleeve 52 carries a cam 84 for the described cam follower 44 of the transfer assembly 42. Cam sleeve 5| carries a cam 85 for follower I1 and cam sleeve 52 carries a cam 86 for follower I8, both followers I1 and I8 being integral with armature member l2 as described above.

Means is also provided for maintaining the delay inserted in the transmission system at a given value for the duration of the transmission of an integral number of complete signal combinations. Cain sleeve 52 carries acam 81 (see Figs. 2 and 3) for a cam follower 89 integral with alever 88 -of tion of thearm 4| of storage member and plates 55 and 56 are slidably carried by, shaft 5 9, the shoulders of the plates being splined together and the assembled plates 55, 56 being splined to the shaft by a screw 58'the tip of which enters a keyway (not shown) in shaft 50. Friction rings 60 are provided between the described friction plates and the described cam sleeves. A single compression spring 6| keeps all friction members under pressure. v p

Cam sleeve 5| is held latched by latching mech- I anism provided as shown in the Zenner et al. patentbut not reproduced here and is released by armature IB' and starting striker l9. Cam sleeve 52 is held latched b-ya' latch armlfl when the arm is in engagement with a tooth on cam 61 (see Figs; 2, 3, and 5). Arocker shaft 68, journaled in the frame plate It, oarriesfixed upon it at one end the cam follower 69 which follows the cam 7 Friction plates 53 and'54 are fixed'to shaft 50 while shoulderedfriction on the first cam sleeve 5| .infront of the frame plate lll, and carries'fixed upon itat the other end the latch arm I0 which engagesithe cam 51 on the second cam sleeve 52 at the backof the frame plateIO. A latch lever I9 for repeater25ihas the form of an-extension arm on a. latch lever member 8| .of yoke form= extending on either side 'ofplate |0;-thetwo yoke arms of which are pivotally supported at the two ends of a studmember fixed in the frame member H]. An extension arm of lever 8| terminates in a cam, follower for the yoke form pivotally supported upon a fixed stud 99 carried by plate Ill one arm of the yoke passing through an opening 96 (see Fig. 1) in the frame plate I!) and being provided with the said integral cam follower 89 and with a notched locking extension 92. A rocking latch 93 pivoted upon a fixed pivot 94 may engage the notch in the extension 92 as illustrated in Figs. 2 and 6 and may be rocked out of latching position by the operation of the describedstrike'r 20 (see Figs. 3'and 6) on armature member I2 upon the receipt of the starting impulse.

Reference to Fig. 7, wherein there is illus-- trated a timing chart for one particular embodiment of the combined repeater mechanism, will demonstrate the necessity for a pluralityof cam sleeves and render the subsequent description of the operation of the apparatus more easily understandable.

In Fig. '7, A represents a start-stop code signal received by magnet I3, the start impulse of which releases first cam sleeve 5|;

B represents the operation of cam 66 and shows at b the release of second cam sleeve 52 one half a signal impulse period after th release of first C represents the actuation of release cam I5 permittingthe positionment of repeater member 25 to correspond to the position already assumed by armature I2 and at 0 there is indicated the release of repeater member 25 one half an impulse period after the reception of the startimpulse, interposing a delay of one half a signal impulse period between the received signal combination and the signal repeated by the first regenerative repeater unit; 7

D represents the cycle of transfer cam 84 and demonstrates at d the transfer of the first, or start, impulse through the transfer mechanism to the second, or storage,regenerative repeater member 35 at a full impulse period after the received start impulse; that is, when the No. 1 signal impulse reaches the repeater magnet, the start impulse is bein transferred to the second regenerative repeater 35; U I Q, g

E illustrates the operation of cam to assist theoperation of the armature I2 and e indicates the operation of follower II by this cam 50 that the armature is under the control of th No. 1 received impulse;

F discloses the operation of release cam 11 which is similar to that of release cam I in point of time but shows the releasing mechanism to be under the control of a cam on sleeve 52 for all signal impulses except the start impulse;

G is a diagram of the cycle of cam 86 for providing assisted armature operation and the cam is actuated in a manner similar to that of cam E except that cam 86 is for those impulses ex clusive of the first impulse;

H and I represent the signals repeated by regenerative repeaters 25 and 35, respectively, and show the delay of one half a signal impulse period in signals transmitted by repeater 25 and a delay of a full signal impulse period in the],

2c 81 to repulse has been fully received by magnet I3 and first cam sleeve 5| is at rest. Hence, if transfer cam 84 were carried by first cam sleeve 5|, the stop impulse would not be transferred to repeater 35 and for that reason a second cam sleeve 52 is provided to accommodate the transfer cam 84.

. At g5 is indicated one time at which the armature I2 is mechanically translated to its attracted position to afiord assisted armature action and it is there clearly illustrated that this is very near the time at which first cam sleeve 5| is arrested, having completed one cycle. Similarly, at f6 there is represented the time at which repeater member 25 is released to be positioned to transmit the stop impulse and this, too, occurs at nearly the time whenthe first cam sleeve 5| is arrested. Although it is possible to arrange V cams 85 and I5 to perform all the armature assisting and releasing operations respectively, the present embodiment of the invention contemplates dividing these operations, as disclosed, between cams 85, 86, and cams 15,". Since the second cam sleeve 52 is necessary as above shown, the additional cams 86 and TI arealso mounted thereon to permit more facile orientation and assure the required time relationships. The particular allocation of operations between cams 85,

86, and cams I5, 11, is not important, and, if desired, cam 85 may be a one tooth cam, as may cam 11. The cams 36 and 11 are provided in order to provide for more certain time relation ships at the times indicated at g5 and 6, respectively.

In the modifications shown in the above-mentioned patent there was illustrated a cam switch at each regenerative repeater, provided to assure that the delay inserted in the transmission circuit be maintained during the transmission of an integral number of complete signal combinations to prevent signal mutilation. Means is provided in the present modification to give the same assurance and it comprises contacts I0 I, I02, and I03, controlled by armature I04 of magnet I65 (see Figs. 1, 6 and 8 Armature I04 has congenerative repeater with a delay of half a signal impulse in the circuit. The locking edge 9| of member 88 operates under the control of cam 81 to maintain armature I04 in the condition existent upon the receipt of the start impulse for the transmission of one entire signal combi-: nation. Curve J demonstrates that the locking edge 9| is not operated to release armature I04 until after the transfer of the stop impulse to repeater 35, at which time first cam sleeve 5| has been arrested and, therefore, second cam sleeve 52 is necessary to provide a release for armature I04 after a signal combination has been fully repeated by repeater as well as re-. peater 25.

Having reference to Fig.8, the combination repeater mechanism disclosed in Figs. 1 to-6, is

shown connected in a circuit comprising a. plu-v rality of substations and a central station. At I20 is represented the central office through which the substations III and II3 are connected for intercommunication. A transmitting distributor I2I is located at the central office and is driven from a speed controlled motor I28 through gearing I29." Thedistributor includes 7 a shaft I22 carrying cams I23, I24, and'IZI opof branch circuits A and B, respectively. Branch A is normally connected.

nected communicationline I|4 to storage repeater 35'introducing a delay of a full signal impulse in the transmission circuit. With armature I04 attracted. line H4 is connected to reerative' to establish and maintain synchronous operation over main channel C in a manner described in the parent application Serial .No. 374,991 previously referred to. Substation III and combination repeater II2 are connected over conductor II4 to central office I20, and substation II3 and combinationrepeater II5 are connected over conductor IIB to the central office. Substation III includes a transmitter II'I (which may be tape controlled or a direct keyboard type); a home recorder H8, and a receiving recorder II9. O-ther substations, for example, II3 included in the circuit arrangement are similar.

In generaL'conductors H4 and H6 form a part circuit A is termed a basic circuit because it is normally conditioned for simplex operation. Reference to Fig; 8 will show that conductor I I4 is normallyconnected directly to conductor I30 of mainchannel' C through the contacts |3l at relay I32 completing a'simplex communication path from a substation III to main channel 0: Main channel C is shown .aspart of a carrier teleei graph system including a; carrier'conductor I33 to which the basic circuit isextended'over conductor I30 and, therefore, it is proper to call conductor I30 an extension conductor to which basic circuit Branch circuit B is termed anadditive circuit because it is normally out of 'the telegraph system but may be added thereto.- Conductor II6 of circuit B, for example, is normally interrupted at the outer right-hand armature of relay I32 and, when relay I32 is energized, circuit B is added to extension conductor I30 in alternation. ,with basic channel II4 through the distributor I2I and its cam controlled contacts. a

As described in the parent application, to initiate'the operation of additive circuit B and thus establish the alternate condition, manual key I34 is closed momentarily to energize relays I35 and- I36 over an obvious circuit. Relay I35 closes its holding contact to form an obvious holding cir-" cuit'for relays I35 and'I36. :Relay I36 operates and connects powerc'onductors 'I3I to the motor I28 thu's'placing the motor: I'28inoperation to,

drive thedistributor shaft I22- U Thereis provided at central 'stationf20 a;plurality of relays, such as :I6I,.one ofwhich is as;v

sociated', with each jextension conductor and which must be operated to convert the extension conductor from simplex tomultiplex operation. The circuit for these relays is closed by slow-tooperate relay I60 when: motor I28 has attained a predetermined speed, as described in the parent application, Serial No. 374,991, filed January 18, 1941. Since relay I60 is slow-to-operate, it will notactuate until the motor I28 attains and holds its synchronous speed. When relay I60 operates, the circuit including relay I6I and others (not shown) for the remaining communication chan-. nels of the system, is completed, thus operating relaylfil preparatory to connecting basic circuit A and additive circuit B to extension conductor I30 through cam controlled-contacts I50 and I54.

When relay I 6I operates, armatures I40 and I M are attracted, thus tacts. Y

The system shown in Fig. 8 has a normal and an alternate condition, the former of which will now be described. Referring toFig. 8, it will be presumed that the mechanical distributor I2I is not operating and thatsubstation III is not transmitting, the entire system being mechane ically inert but being in a condition of electrical preparedness. Magnet I3 is held energized by current in a circuit through the transmitter at substation I I I. Magnet .I05is de-energized because its circuit including contacts I38, conductor I39, right-handwinding of relay I32, armature I40, line I42, contacts I43 at cam I24, line I44,- and ground is open at armature I40. Magnet I46 is held energized by current in acircuit including conductor I41, contacts I48 and conductor I49-to closing theirassociated conground.

Upon generation of a permutation code signal at substation I II, magnet I3 is de-energized at the beginning ofthe start impulse. Armature I6 (see Fig.1) is released and striker I9 (Fig. 3) re-' leases the first cam sleeve .5I as described in the Zenneret al. patent. Release of armature I6 also operates armature member :I2 clockwise under the force of spring 34 and striker 20 which en-' gages and rocks the latch 93 (Fig.6) to release the locking member 88 which, urged by the tension of spring'95, engages the armature I04, preventing the shifting of the contact spring I during the period of "transmission; of they then ensuing code signal. Because of the movement.

ofarmature member I2, one of the springs 83 now tensions the repeater member 25 against the latch 19.

After a delayof one-half signal impulsetime period, cam 15 operates the follower 16 and latch 19 as described in the Zenner et al. patent, and the cam 66 operates the follower 69 to rock the shaft 68 and latch 10, thus releasing the second cam sleeve 52 with a delay of one-halfsignal impulse time period after the release of. the first cam sleeve Latch 19 momentarily releases the repeater member 25 which shiftsits abutments 29, 30 and also operates its electrical .con'-.. tacts 26 thus repeating the starting signal impulse into :the contacts26 with 'atime delay of;

one-half signalimpulse period as compared with the original signal impulse. l I *After a further delay of approximately one half signal impulse time period from the instant of operation of-the'contacts 26, and just'prece'ding the beginning of the No; 1"character.-codeim-- pulse of the permutationcodesignal, presumed to be an-impulse of marking ,signalnature, cam fl4 operateszit's follower 4.4 which propels the. T141 against the shifted abutment -29. andbyxthe re sultant rocking of the T 41 effects a shifting of arm H and storage member 35 to repeat the starting signal impulse into the contacts 29 with a time delay of one full signal impulse period as compared with the original signal impulse.

The first impulse is then received, energizing magnet I3 but with the holding type magnet employed, the magnet is not strong enough to at tractits armature. After the No. 1 impulse has been sustained for nearly half a signal impulse period, cam 85 operates its follower I1 to restore armature member I2 to its attracted position as described in the Zenner et al. patent, thus causing spring 62 to tension repeater member for a marking signal impulse. Since a marking impulse'is being-received, magnet I3 now retains armature I2 in its attracted position. The employment of a holding magnet of this nature enables the multiplex to be conditioned by only a part of the received signals and consequently, limited mutilation of the received signals is eliminated and not transferred into the multiplex system.

'At' an instant one-half signal impulse time period after the beginning of the No. 1 impulse in magnet I3, cam 11 operates its follower 18 and latch 19 to momentarily release the repeater member 25 which is then shifted by spring 82 to repeat the marking impulse into contacts 26 and to shift abutments 29 and 30. At an instant approximately one full signal impulse time period after the beginning of the No. 1 impulse in magnet I 3, cam 84 operates its follower 44 and propels' the transfer T 41 against restored abutment 30 to operate the storage repeater member and to repeat theNo. 1 signal impulse into the contacts 39 with a delay of one full signal impulse time period after the beginning of the No. 1 signal impulse in magnet I3. In likemanner the V remaining'impulses of the signal combination are repeated at contacts 26 and 39.

During the time period of the stop impulse of the received code signal the first cam sleeve 5I is stopped by stop arm 14 as described in the Zenner et al. patent and one-half signal impulse period later the second camsleeve 52is stopped byengagement of cam tooth 61 with. latch arm 10. Just before the second cam sleeve 52 stops, cam 81 engages its follower 89 and shifts the locking member 88 into position to release the armature I04 in which position the locking member 88 is engaged by locking latch 92 and is re-' strained pending receipt of a starting impulseby the magnet I3. All apparatus is again at rest.

During the receipt and retransmission of each successive code. signal, the'signal impulses are repeated into contacts 26 with a delay of .onehalf impulse period and also are repeated into contacts 39 with a delay of one full impulse period. The position of contact spring IOI determines whether the basic circuit II4 shall be connected-to contacts 26 for retransmission with a delay of one-half impulse period or tocontacts 39 for retransmission with a delay of one full impulse period. The position of contact spring I BI is determined by the position of armature I04-at the instant that the locking member 88 is unlatched-by the armature I6 acting through striker 26 and latch 93 in response to a received starting impulse of a code signal combination.

In the normal condition of the particular embodiment of the invention under consideration, magnet I05 is tie-energized, as illustrated in Fig. 4 and accordingly, line H4 isconnected to storage I 05, I43, receive impulses of current in uninterrupted sequence from contacts I43, I 48, of cam The signal impulses for the basic circuitaare transmitted through contacts I50 (see Fig. 8).

Should the beginning of the start, impulse in magnet I3 occur with distributor I 2| operating and with the distributor cams I23 and I24 transiently in the position shown with contacts I50 closed and contacts I43open, conductor I 42 would be open at contact I43 of cam I24, magnet I would be de-energized and contact IOI would be in engagement with contact I03, as shown, connecting conductor I I4 to contacts 39 of storage regenerative repeater 35. At a half impulse period later, the contact I50 will be found open and the starting impulse will be transmitted into contacts I5I ineffectively. At a further half impulse period later the contact I50 will be found closed and the starting impulse will be transmitted into contacts I52, thence through contacts I03, IOI, conductor II4, contacts of operated relay I32, contact I50 and extension conductor I to line transmitting relay I53. Upon the receipt of the start impulse, locking lever 88 operates and holds armature I04 immobile during the ensuing signal combination.

Should the beginning of thestart impulse in magnet I3 occur with distributor I2I operating and with the distributor cam I23 transiently in its position alternative to that shown, with contacts I open, conductor I42 would be closed at contact I43, magnet I05 would be energized and contact IOI would be in engagement with contact I02 connecting line conductor II4 to the regenerative repeater 25. At a half impulse period later, the contact I50 will be found closed and the starting impulse will be transmitted into contacts 26 thence through contacts I02, IOI, conductor I I4, contacts of operated relay I32, contact I50 and extension conductor I30 to line transmitting relay I53. Signal impulses will be repeated into contacts 39 but without effect since they are disconnected from the line. The operation of combination repeater I I5 is identical with operation of repeater II 2, transmission being over conductor I I6 of the additive circuit and contacts I54 of cam I23 to relay I53.

At the end of each revolution of second cam sleeve 52 the cam 81 engages its follower 89 and operates the locking member 88, withdrawing the .locking edge 9I from engagement with armature I04, permitting the armature I04 to respond to magnet I05 according to the energized or unenergized condition of the magnet I05. The contact spring IOI thus may be readjusted invariably by the transmitting phasing cam I24 between successive code signals even though the successive code signals are continuous as would be the condition with a tape controlled transmitter operating at station I I I.

Locking lever 88 carries two contact operating devices, shown diagrammatically in Fig. 8, for operating contacts 138 and I to prevent signal multilation by converting to multiplex operation during the transmission of a signal combination ceipt. of a start impulse by magnet! 3, latch 93 is rocked and lever 88 rotates counterclockwise under the influence of spring 95 disengaging contacts I38 and I55. Should key I34 be depressed at this time, the establishment'of multiplex operation would be delayed because the circuits to the energizing windings of relay I 32 are disabled at contacts, I38, and I55. Upon the re- .ceipt ofthe stop impulse, member 88 is rotated clockwise by cam '01 and closes contacts I .38 and I55 permitting relay I32 tobeenergized over a the circuit including battery, magnet I05, conto repeater contacts with the operation of contacts I50. consequent tacts I38, line I39 and right-hand winding of relay I32 or the circuit including battery, contacts I55, line I56 and center'winding of relay I32.

From relay I32, each circuit is 'comple'ted'through contact 'I43,' line I44 andground- Accordingly, conditioning the system for the multiplex operation may be accomplished without interrupting transmission over the basic circuit.

, When the system is" conditioned for multiplex operation and one ofthe branches, sayline H4,

is idle, the transmitting phasing cam I24 through contact I43, lines I42 and I39 alternatelyener gize's and de-ene'rgizesmagnet I05, vibrating armature I04 and connecting line I I4alternately 26'and39 in phase relation ly,' when the multiplex condition is once established, it is maintained and no, matter when transmission is resumed on line H4, it will be properly phased with respectto the operation of regularly operated contacts I50.

What is claimed is:'

1. In a repeater, means in said repeater to generate a first set of signals corresponding to 'signals received by said repeatenmeans in said repeater to generate a second set. of signals iden- 40 tical with but lagging by a predetermined time interval said first set of regenerated signals, and

means cooperating with said repeater to .trans+ mit either one of said sets of regenerated signals.

2. A telegraph repeater capable of generating two signal impulses or each. received signal im pulse comprising a magnetiforreceiving signal impulses, an armature positioned in' accordance with the operation 'of "said magnet, a first set of output contacts, mechanism operable after said magnet has positioned its armature to operate said first set of output contacts to generate a first signal corresponding to areceived signal, a

second set of output contacts, and further mechanisms operable after the operation of said first mechanism and under the control of said first set of output contacts to operate said second set of output contacts to generate a second signal corresponding to said received signal.

. 3. In a communication system, a telegraph circuit, a start-stop repeater, means in said repeater to generate a first set of signals under the control of incoming signals, means controlled by said signal generating means to generate a second set of signals like the first but shifted in phase,

' means to connect one or the other of said sets of signals to said telegraph circuit, and means to operate said last mentioned means onlywhen said first signal generating means are inoperative.

4. In a telegraph system, a transmitter, a repeater, a telegraph circuit including said transmitter and said repeater, means in said repeater to generate one set of signals in response to signals emitted by said transmitter, means in said repeater to generate a second set of signals like over the basic circuit. That is, upon the re- 6 the first set'but shifted in phase, and means operating in phase with signals emitted'by said transmitter to connect'one or the other of said generating means to said telegraph circuit.

5. Themethod of repeating; from a random timed signal source to an independently timed output which comprises the steps of generating two sets of signals from the source but differing in phase, and. selecting that set for controlling the output which bears a suitable time relation [to the outgoing timed source so as to pass the V signals without mutilation.

6. Theimethod of repeating from a random 'timedsignal source of a periodically timed reerating random timed signals, an independently timed outgoing circuit, timing means in said circuit, means for repeating fromsaid random 7 ltimed signal generating means to said independentlyv timed outgoing circuit, means to generate under control of each random timed signal two corresponding signals, means to invariably maint'aina fixed lag between saidtwo corresponding signals, and means to select one of said two corresponding signalsto control transmission on the independently timed outgoing circuit according to the time of arrival of the random timed signal with respect to the phase of said timing means.

' 8. In a regenerative repeater, means for generating random timed signals comprising permutation code combinations of signaling impulses, a synchronous multiplex circuit, means for repeating from saidrandom timed signal generating means to a channel of said multiplex circuit, means to generate under control of each random timed signal two corresponding signals, and means to invariably maintain a fixedla-g-of less than an elemental code'impulse interval between said two corresponding signals.

i "9. In a regenerative repeater, means-for generating random timed signals comprising permutation code combinations of signaling impulses,

an independently timed output circuit, means for repeating from said random timed signal generating means to said independently timed output' circuit, means to generate under control of each random timed signal two corresponding signals, means to invariably maintain a fixed lag between said two corresponding signals, means effective at the beginning of a 0 Signal o Select one of said two corresponding signals to control the signal on the independently timed output circuit, and means to maintain said selection until the repeating of said code signal is completed.

10. In a regenerative repeater for a multiplex start-stop extension circuit system comprising means for generating random timed start-stop permutation code signals, an independently timed outgoing circuit, transmitting means in said circuit, means to generate'a plurality of sets of startstop permutation code signals similar to the random timed start-stop permutation code signals, and means to cause one of said sets of start-stop permutation code signals to lag behind the other, whereby at least, one of said sets of signals is invariably in a suitable phase for said transmitting means to pick up those signals without mutilationl 11. The method of repeating from a signal source to an outgoing circuit which comprises the steps of generating a plurality of similar signals under control of a single signal from said source, varying the phase of each of said similar signals, and selecting'one of said similar signals for transmission on the outgoing circuit.

12. The method of repeating from a permutation code signal source to an outgoing circuit which comprises the steps of generating a plurality of similar permutation code signals under control of a single permutation code signal from said source, varying the phase of each of said similar permutation code signals, selecting one of said similar signals for transmission on said outgoing circuit, and maintaining the same selection during an entire permutation code time interval.

LOUIS M. POTTS, 

